This invention relates to an integrated thermal buckling micro switch, particularly to the integrated thermal buckling micro switch wherein the sensors and actuators are integrated and arranged on a single chip by using micro electromechanical technology.
A conventional thermal buckling switch is usually constructed in a mechanical bimetal structure, wherein two kinds of metal with different thermal expansion coefficients are combined. When the switch is heated to some extent, two contact points of the bi-metal structure will depart from or embrace each other to cut off or drive a circuit.
The thermal buckling switch of mechanical bimetal structure can hardly be pre-set to act at a precise temperature, it is supposed to buckle within a temperature range instead, hence, it only fits systems that require rough temperature control.
In addition, elastic fatigue of a bimetal may come out after repeated expansion and shrinkage to blunt its sensitivity.
Furthermore, the thermal buckling switch of mechanical bimetal structure usually requires extra cooperative mechanical parts that may slow down response of the switch, and besides, its bulky volume and high cost will inevitably reduce its competition capability in the market, and the worst part is that it can hardly be